21131034204 has 72 divisors (see below), whose sum is σ = 60729555600. Its totient is φ = 5682292224.

The previous prime is 21131034193. The next prime is 21131034229. The reversal of 21131034204 is 40243013112.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1046979 + ... + 1066970.

It is an arithmetic number, because the mean of its divisors is an integer number (843466050).

Almost surely, 2^21131034204 is an apocalyptic number.

It is an amenable number.

21131034204 is an abundant number, since it is smaller than the sum of its proper divisors (39598521396).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21131034204 is a wasteful number, since it uses less digits than its factorization.

21131034204 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2113987 (or 2113978 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 21.

Adding to 21131034204 its reverse (40243013112), we get a palindrome (61374047316).

The spelling of 21131034204 in words is "twenty-one billion, one hundred thirty-one million, thirty-four thousand, two hundred four".